master
1/* $NetBSD: ext2fs.h,v 1.48 2016/08/20 19:47:44 jdolecek Exp $ */
2
3/*
4 * Copyright (c) 1982, 1986, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)fs.h 8.10 (Berkeley) 10/27/94
32 * Modified for ext2fs by Manuel Bouyer.
33 */
34
35/*
36 * Copyright (c) 1997 Manuel Bouyer.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
48 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
50 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
51 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
52 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
53 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
54 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
55 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
56 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
57 *
58 * @(#)fs.h 8.10 (Berkeley) 10/27/94
59 * Modified for ext2fs by Manuel Bouyer.
60 */
61
62#ifndef _UFS_EXT2FS_EXT2FS_H_
63#define _UFS_EXT2FS_EXT2FS_H_
64
65#include <sys/bswap.h>
66
67/*
68 * Each disk drive contains some number of file systems.
69 * A file system consists of a number of cylinder groups.
70 * Each cylinder group has inodes and data.
71 *
72 * A file system is described by its super-block, which in turn
73 * describes the cylinder groups. The super-block is critical
74 * data and is replicated in each cylinder group to protect against
75 * catastrophic loss. This is done at `newfs' time and the critical
76 * super-block data does not change, so the copies need not be
77 * referenced further unless disaster strikes.
78 *
79 * The first boot and super blocks are given in absolute disk addresses.
80 * The byte-offset forms are preferred, as they don't imply a sector size.
81 */
82#define BBSIZE 1024
83#define SBSIZE 1024
84#define BBOFF ((off_t)(0))
85#define SBOFF ((off_t)(BBOFF + BBSIZE))
86#define BBLOCK ((daddr_t)(0))
87#define SBLOCK ((daddr_t)(BBLOCK + BBSIZE / DEV_BSIZE))
88
89#define fsbtodb(fs, b) ((daddr_t)(b) << (fs)->e2fs_fsbtodb)
90/* calculates (loc / fs->fs_bsize) */
91#define lblkno(fs, loc) ((loc) >> (fs->e2fs_bshift))
92#define blksize(fs, ip, lbn) ((fs)->e2fs_bsize)
93
94/*
95 * Addresses stored in inodes are capable of addressing blocks
96 * XXX
97 */
98
99/*
100 * MINBSIZE is the smallest allowable block size.
101 * MINBSIZE must be big enough to hold a cylinder group block,
102 * thus changes to (struct cg) must keep its size within MINBSIZE.
103 * Note that super blocks are always of size SBSIZE,
104 * and that both SBSIZE and MAXBSIZE must be >= MINBSIZE.
105 */
106#define LOG_MINBSIZE 10
107#define MINBSIZE (1 << LOG_MINBSIZE)
108
109/*
110 * The path name on which the file system is mounted is maintained
111 * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
112 * the super block for this name.
113 */
114#define MAXMNTLEN 512
115
116/*
117 * MINFREE gives the minimum acceptable percentage of file system
118 * blocks which may be free. If the freelist drops below this level
119 * only the superuser may continue to allocate blocks. This may
120 * be set to 0 if no reserve of free blocks is deemed necessary,
121 * however throughput drops by fifty percent if the file system
122 * is run at between 95% and 100% full; thus the minimum default
123 * value of fs_minfree is 5%. However, to get good clustering
124 * performance, 10% is a better choice. hence we use 10% as our
125 * default value. With 10% free space, fragmentation is not a
126 * problem, so we choose to optimize for time.
127 */
128#define MINFREE 5
129
130/*
131 * This is maximum amount of links allowed for files. For directories,
132 * going over this means setting DIR_NLINK feature.
133 */
134#define EXT2FS_LINK_MAX 65000
135#define EXT2FS_LINK_INF 1 /* link count unknown */
136
137/*
138 * Super block for an ext2fs file system.
139 */
140struct ext2fs {
141 uint32_t e2fs_icount; /* Inode count */
142 uint32_t e2fs_bcount; /* blocks count */
143 uint32_t e2fs_rbcount; /* reserved blocks count */
144 uint32_t e2fs_fbcount; /* free blocks count */
145 uint32_t e2fs_ficount; /* free inodes count */
146 uint32_t e2fs_first_dblock; /* first data block */
147 uint32_t e2fs_log_bsize; /* bsize = 1024*(2^e2fs_log_bsize) */
148 uint32_t e2fs_fsize; /* fragment size */
149 uint32_t e2fs_bpg; /* blocks per group */
150 uint32_t e2fs_fpg; /* frags per group */
151 uint32_t e2fs_ipg; /* inodes per group */
152 uint32_t e2fs_mtime; /* mount time */
153 uint32_t e2fs_wtime; /* write time */
154 uint16_t e2fs_mnt_count; /* mount count */
155 uint16_t e2fs_max_mnt_count; /* max mount count */
156 uint16_t e2fs_magic; /* magic number */
157 uint16_t e2fs_state; /* file system state */
158 uint16_t e2fs_beh; /* behavior on errors */
159 uint16_t e2fs_minrev; /* minor revision level */
160 uint32_t e2fs_lastfsck; /* time of last fsck */
161 uint32_t e2fs_fsckintv; /* max time between fscks */
162 uint32_t e2fs_creator; /* creator OS */
163 uint32_t e2fs_rev; /* revision level */
164 uint16_t e2fs_ruid; /* default uid for reserved blocks */
165 uint16_t e2fs_rgid; /* default gid for reserved blocks */
166 /* EXT2_DYNAMIC_REV superblocks */
167 uint32_t e2fs_first_ino; /* first non-reserved inode */
168 uint16_t e2fs_inode_size; /* size of inode structure */
169 uint16_t e2fs_block_group_nr; /* block grp number of this sblk*/
170 uint32_t e2fs_features_compat; /* compatible feature set */
171 uint32_t e2fs_features_incompat; /* incompatible feature set */
172 uint32_t e2fs_features_rocompat; /* RO-compatible feature set */
173 uint8_t e2fs_uuid[16]; /* 128-bit uuid for volume */
174 char e2fs_vname[16]; /* volume name */
175 char e2fs_fsmnt[64]; /* name mounted on */
176 uint32_t e2fs_algo; /* For compression */
177 uint8_t e2fs_prealloc; /* # of blocks to preallocate */
178 uint8_t e2fs_dir_prealloc; /* # of blocks to preallocate for dir */
179 uint16_t e2fs_reserved_ngdb; /* # of reserved gd blocks for resize */
180
181 /* Additional fields */
182 char e3fs_journal_uuid[16];/* uuid of journal superblock */
183 uint32_t e3fs_journal_inum; /* inode number of journal file */
184 uint32_t e3fs_journal_dev; /* device number of journal file */
185 uint32_t e3fs_last_orphan; /* start of list of inodes to delete */
186 uint32_t e3fs_hash_seed[4]; /* HTREE hash seed */
187 char e3fs_def_hash_version;/* Default hash version to use */
188 char e3fs_jnl_backup_type;
189 uint16_t e3fs_desc_size; /* size of group descriptor */
190 uint32_t e3fs_default_mount_opts;
191 uint32_t e3fs_first_meta_bg; /* First metablock block group */
192 uint32_t e3fs_mkfs_time; /* when the fs was created */
193 uint32_t e3fs_jnl_blks[17]; /* backup of the journal inode */
194 uint32_t e4fs_bcount_hi; /* high bits of blocks count */
195 uint32_t e4fs_rbcount_hi; /* high bits of reserved blocks count */
196 uint32_t e4fs_fbcount_hi; /* high bits of free blocks count */
197 uint16_t e4fs_min_extra_isize; /* all inodes have some bytes */
198 uint16_t e4fs_want_extra_isize;/* inodes must reserve some bytes */
199 uint32_t e4fs_flags; /* miscellaneous flags */
200 uint16_t e4fs_raid_stride; /* RAID stride */
201 uint16_t e4fs_mmpintv; /* seconds to wait in MMP checking */
202 uint64_t e4fs_mmpblk; /* block for multi-mount protection */
203 uint32_t e4fs_raid_stripe_wid; /* blocks on data disks (N * stride) */
204 uint8_t e4fs_log_gpf; /* FLEX_BG group size */
205 uint8_t e4fs_chksum_type; /* metadata checksum algorithm used */
206 uint8_t e4fs_encrypt; /* versioning level for encryption */
207 uint8_t e4fs_reserved_pad;
208 uint64_t e4fs_kbytes_written; /* number of lifetime kilobytes */
209 uint32_t e4fs_snapinum; /* inode number of active snapshot */
210 uint32_t e4fs_snapid; /* sequential ID of active snapshot */
211 uint64_t e4fs_snaprbcount; /* rsvd blocks for active snapshot */
212 uint32_t e4fs_snaplist; /* inode number for on-disk snapshot */
213 uint32_t e4fs_errcount; /* number of file system errors */
214 uint32_t e4fs_first_errtime; /* first time an error happened */
215 uint32_t e4fs_first_errino; /* inode involved in first error */
216 uint64_t e4fs_first_errblk; /* block involved of first error */
217 uint8_t e4fs_first_errfunc[32];/* function where error happened */
218 uint32_t e4fs_first_errline; /* line number where error happened */
219 uint32_t e4fs_last_errtime; /* most recent time of an error */
220 uint32_t e4fs_last_errino; /* inode involved in last error */
221 uint32_t e4fs_last_errline; /* line number where error happened */
222 uint64_t e4fs_last_errblk; /* block involved of last error */
223 uint8_t e4fs_last_errfunc[32];/* function where error happened */
224 uint8_t e4fs_mount_opts[64];
225 uint32_t e4fs_usrquota_inum; /* inode for tracking user quota */
226 uint32_t e4fs_grpquota_inum; /* inode for tracking group quota */
227 uint32_t e4fs_overhead_clusters;/* overhead blocks/clusters */
228 uint32_t e4fs_backup_bgs[2]; /* groups with sparse_super2 SBs */
229 uint8_t e4fs_encrypt_algos[4];/* encryption algorithms in use */
230 uint8_t e4fs_encrypt_pw_salt[16];/* salt used for string2key */
231 uint32_t e4fs_lpf_ino; /* location of the lost+found inode */
232 uint32_t e4fs_proj_quota_inum; /* inode for tracking project quota */
233 uint32_t e4fs_chksum_seed; /* checksum seed */
234 uint32_t e4fs_reserved[98]; /* padding to the end of the block */
235 uint32_t e4fs_sbchksum; /* superblock checksum */
236};
237
238
239/* in-memory data for ext2fs */
240struct m_ext2fs {
241 struct ext2fs e2fs;
242 u_char e2fs_fsmnt[MAXMNTLEN]; /* name mounted on */
243 int8_t e2fs_ronly; /* mounted read-only flag */
244 int8_t e2fs_fmod; /* super block modified flag */
245 int8_t e2fs_uhash; /* 3 if hash should be signed, 0 if not */
246 int32_t e2fs_bsize; /* block size */
247 int32_t e2fs_bshift; /* ``lblkno'' calc of logical blkno */
248 int32_t e2fs_bmask; /* ``blkoff'' calc of blk offsets */
249 int64_t e2fs_qbmask; /* ~fs_bmask - for use with quad size */
250 int32_t e2fs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
251 int32_t e2fs_ncg; /* number of cylinder groups */
252 int32_t e2fs_ngdb; /* number of group descriptor blocks */
253 int32_t e2fs_ipb; /* number of inodes per block */
254 int32_t e2fs_itpg; /* number of inode table blocks per group */
255 struct ext2_gd *e2fs_gd; /* group descriptors (data not byteswapped) */
256};
257
258
259
260/*
261 * Filesystem identification
262 */
263#define E2FS_MAGIC 0xef53 /* the ext2fs magic number */
264#define E2FS_REV0 0 /* GOOD_OLD revision */
265#define E2FS_REV1 1 /* Support compat/incompat features */
266
267/* compatible/incompatible features */
268#define EXT2F_COMPAT_PREALLOC 0x0001
269#define EXT2F_COMPAT_AFS 0x0002
270#define EXT2F_COMPAT_HASJOURNAL 0x0004
271#define EXT2F_COMPAT_EXTATTR 0x0008
272#define EXT2F_COMPAT_RESIZE 0x0010
273#define EXT2F_COMPAT_DIRHASHINDEX 0x0020
274#define EXT2F_COMPAT_SPARSESUPER2 0x0200
275#define EXT2F_COMPAT_BITS \
276 "\20" \
277 "\12COMPAT_SPARSESUPER2" \
278 "\11" \
279 "\10" \
280 "\07" \
281 "\06COMPAT_DIRHASHINDEX" \
282 "\05COMPAT_RESIZE" \
283 "\04COMPAT_EXTATTR" \
284 "\03COMPAT_HASJOURNAL" \
285 "\02COMPAT_AFS" \
286 "\01COMPAT_PREALLOC"
287
288#define EXT2F_ROCOMPAT_SPARSESUPER 0x0001
289#define EXT2F_ROCOMPAT_LARGEFILE 0x0002
290#define EXT2F_ROCOMPAT_BTREE_DIR 0x0004
291#define EXT2F_ROCOMPAT_HUGE_FILE 0x0008
292#define EXT2F_ROCOMPAT_GDT_CSUM 0x0010
293#define EXT2F_ROCOMPAT_DIR_NLINK 0x0020
294#define EXT2F_ROCOMPAT_EXTRA_ISIZE 0x0040
295#define EXT2F_ROCOMPAT_QUOTA 0x0100
296#define EXT2F_ROCOMPAT_BIGALLOC 0x0200
297#define EXT2F_ROCOMPAT_METADATA_CKSUM 0x0400
298#define EXT2F_ROCOMPAT_READONLY 0x1000
299#define EXT2F_ROCOMPAT_PROJECT 0x2000
300#define EXT2F_ROCOMPAT_BITS \
301 "\20" \
302 "\16ROCOMPAT_PROJECT" \
303 "\15ROCOMPAT_READONLY" \
304 "\14" \
305 "\13ROCOMPAT_METADATA_CKSUM" \
306 "\12ROCOMPAT_BIGALLOC" \
307 "\11ROCOMPAT_QUOTA" \
308 "\10" \
309 "\07ROCOMPAT_EXTRA_ISIZE" \
310 "\06ROCOMPAT_DIR_NLINK" \
311 "\05ROCOMPAT_GDT_CSUM" \
312 "\04ROCOMPAT_HUGE_FILE" \
313 "\03ROCOMPAT_BTREE_DIR" \
314 "\02ROCOMPAT_LARGEFILE" \
315 "\01ROCOMPAT_SPARSESUPER"
316
317#define EXT2F_INCOMPAT_COMP 0x0001
318#define EXT2F_INCOMPAT_FTYPE 0x0002
319#define EXT2F_INCOMPAT_REPLAY_JOURNAL 0x0004
320#define EXT2F_INCOMPAT_USES_JOURNAL 0x0008
321#define EXT2F_INCOMPAT_META_BG 0x0010
322#define EXT2F_INCOMPAT_EXTENTS 0x0040
323#define EXT2F_INCOMPAT_64BIT 0x0080
324#define EXT2F_INCOMPAT_MMP 0x0100
325#define EXT2F_INCOMPAT_FLEX_BG 0x0200
326#define EXT2F_INCOMPAT_EA_INODE 0x0400
327#define EXT2F_INCOMPAT_DIRDATA 0x1000
328#define EXT2F_INCOMPAT_CSUM_SEED 0x2000
329#define EXT2F_INCOMPAT_LARGEDIR 0x4000
330#define EXT2F_INCOMPAT_INLINE_DATA 0x8000
331#define EXT2F_INCOMPAT_ENCRYPT 0x10000
332#define EXT2F_INCOMPAT_BITS \
333 "\20" \
334 "\021INCOMPAT_ENCRYPT" \
335 "\020INCOMPAT_INLINE_DATA" \
336 "\017INCOMPAT_LARGEDIR" \
337 "\016INCOMPAT_CSUM_SEED" \
338 "\015INCOMPAT_DIRDATA" \
339 "\014" \
340 "\013INCOMPAT_EA_INODE" \
341 "\012INCOMPAT_FLEX_BG" \
342 "\011INCOMPAT_MMP" \
343 "\010INCOMPAT_64BIT" \
344 "\07INCOMPAT_EXTENTS" \
345 "\05INCOMPAT_META_BG" \
346 "\04INCOMPAT_USES_JOURNAL" \
347 "\03INCOMPAT_REPLAY_JOURNAL" \
348 "\02INCOMPAT_FTYPE" \
349 "\01INCOMPAT_COMP"
350
351/*
352 * Features supported in this implementation
353 *
354 * We support the following REV1 features:
355 * - EXT2F_ROCOMPAT_SPARSESUPER
356 * superblock backups stored only in cg_has_sb(bno) groups
357 * - EXT2F_ROCOMPAT_LARGEFILE
358 * use e2di_size_high in struct ext2fs_dinode to store
359 * upper 32bit of size for >2GB files
360 * - EXT2F_INCOMPAT_FTYPE
361 * store file type to e2d_type in struct ext2fs_direct
362 * (on REV0 e2d_namlen is uint16_t and no e2d_type, like ffs)
363 */
364#define EXT2F_COMPAT_SUPP 0x0000
365#define EXT2F_ROCOMPAT_SUPP (EXT2F_ROCOMPAT_SPARSESUPER \
366 | EXT2F_ROCOMPAT_LARGEFILE \
367 | EXT2F_ROCOMPAT_HUGE_FILE \
368 | EXT2F_ROCOMPAT_EXTRA_ISIZE \
369 | EXT2F_ROCOMPAT_DIR_NLINK \
370 | EXT2F_ROCOMPAT_GDT_CSUM)
371#define EXT2F_INCOMPAT_SUPP (EXT2F_INCOMPAT_FTYPE \
372 | EXT2F_INCOMPAT_EXTENTS \
373 | EXT2F_INCOMPAT_FLEX_BG)
374
375/*
376 * Feature set definitions
377 */
378#define EXT2F_HAS_COMPAT_FEATURE(fs, feature) \
379 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \
380 ((fs)->e2fs.e2fs_features_compat & (feature)) != 0)
381
382#define EXT2F_HAS_ROCOMPAT_FEATURE(fs, feature) \
383 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \
384 ((fs)->e2fs.e2fs_features_rocompat & (feature)) != 0)
385
386#define EXT2F_HAS_INCOMPAT_FEATURE(fs, feature) \
387 ((fs)->e2fs.e2fs_rev >= E2FS_REV1 && \
388 ((fs)->e2fs.e2fs_features_incompat & (feature)) != 0)
389
390
391/*
392 * Definitions of behavior on errors
393 */
394#define E2FS_BEH_CONTINUE 1 /* continue operation */
395#define E2FS_BEH_READONLY 2 /* remount fs read only */
396#define E2FS_BEH_PANIC 3 /* cause panic */
397#define E2FS_BEH_DEFAULT E2FS_BEH_CONTINUE
398
399/*
400 * OS identification
401 */
402#define E2FS_OS_LINUX 0
403#define E2FS_OS_HURD 1
404#define E2FS_OS_MASIX 2
405#define E2FS_OS_FREEBSD 3
406#define E2FS_OS_LITES 4
407
408/*
409 * Filesystem clean flags
410 */
411#define E2FS_ISCLEAN 0x01
412#define E2FS_ERRORS 0x02
413
414/* ext2 file system block group descriptor */
415
416struct ext2_gd {
417 uint32_t ext2bgd_b_bitmap; /* blocks bitmap block */
418 uint32_t ext2bgd_i_bitmap; /* inodes bitmap block */
419 uint32_t ext2bgd_i_tables; /* first inodes table block */
420 uint16_t ext2bgd_nbfree; /* number of free blocks */
421 uint16_t ext2bgd_nifree; /* number of free inodes */
422 uint16_t ext2bgd_ndirs; /* number of directories */
423
424 /*
425 * Following only valid when either GDT_CSUM (AKA uninit_bg)
426 * or METADATA_CKSUM feature is on
427 */
428 uint16_t ext2bgd_flags; /* ext4 bg flags (INODE_UNINIT, ...)*/
429 uint32_t ext2bgd_exclude_bitmap_lo; /* snapshot exclude bitmap */
430 uint16_t ext2bgd_block_bitmap_csum_lo; /* Low block bitmap checksum */
431 uint16_t ext2bgd_inode_bitmap_csum_lo; /* Low inode bitmap checksum */
432 uint16_t ext2bgd_itable_unused_lo; /* Low unused inode offset */
433 uint16_t ext2bgd_checksum; /* Group desc checksum */
434
435 /*
436 * XXX disk32 Further fields only exist if 64BIT feature is on
437 * and superblock desc_size > 32, not supported for now.
438 */
439};
440
441#define E2FS_BG_INODE_UNINIT 0x0001 /* Inode bitmap not used/initialized */
442#define E2FS_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not used/initialized */
443#define E2FS_BG_INODE_ZEROED 0x0004 /* On-disk inode table initialized */
444
445#define E2FS_HAS_GD_CSUM(fs) \
446 EXT2F_HAS_ROCOMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM|EXT2F_ROCOMPAT_METADATA_CKSUM) != 0
447
448/*
449 * If the EXT2F_ROCOMPAT_SPARSESUPER flag is set, the cylinder group has a
450 * copy of the super and cylinder group descriptors blocks only if it's
451 * 1, a power of 3, 5 or 7
452 */
453
454static __inline int cg_has_sb(int) __unused;
455static __inline int
456cg_has_sb(int i)
457{
458 int a3, a5, a7;
459
460 if (i == 0 || i == 1)
461 return 1;
462 for (a3 = 3, a5 = 5, a7 = 7;
463 a3 <= i || a5 <= i || a7 <= i;
464 a3 *= 3, a5 *= 5, a7 *= 7)
465 if (i == a3 || i == a5 || i == a7)
466 return 1;
467 return 0;
468}
469
470/* EXT2FS metadatas are stored in little-endian byte order. These macros
471 * helps reading theses metadatas
472 */
473
474#if BYTE_ORDER == LITTLE_ENDIAN
475# define h2fs16(x) (x)
476# define h2fs32(x) (x)
477# define h2fs64(x) (x)
478# define fs2h16(x) (x)
479# define fs2h32(x) (x)
480# define fs2h64(x) (x)
481# define e2fs_sbload(old, new) memcpy((new), (old), SBSIZE)
482# define e2fs_sbsave(old, new) memcpy((new), (old), SBSIZE)
483#else
484void e2fs_sb_bswap(struct ext2fs *, struct ext2fs *);
485# define h2fs16(x) bswap16(x)
486# define h2fs32(x) bswap32(x)
487# define h2fs64(x) bswap64(x)
488# define fs2h16(x) bswap16(x)
489# define fs2h32(x) bswap32(x)
490# define fs2h64(x) bswap64(x)
491# define e2fs_sbload(old, new) e2fs_sb_bswap((old), (new))
492# define e2fs_sbsave(old, new) e2fs_sb_bswap((old), (new))
493#endif
494
495/* Group descriptors are not byte swapped */
496#define e2fs_cgload(old, new, size) memcpy((new), (old), (size))
497#define e2fs_cgsave(old, new, size) memcpy((new), (old), (size))
498
499/*
500 * Turn file system block numbers into disk block addresses.
501 * This maps file system blocks to device size blocks.
502 */
503#define EXT2_FSBTODB(fs, b) ((b) << (fs)->e2fs_fsbtodb)
504#define EXT2_DBTOFSB(fs, b) ((b) >> (fs)->e2fs_fsbtodb)
505
506/*
507 * Macros for handling inode numbers:
508 * inode number to file system block offset.
509 * inode number to cylinder group number.
510 * inode number to file system block address.
511 */
512#define ino_to_cg(fs, x) (((x) - 1) / (fs)->e2fs.e2fs_ipg)
513#define ino_to_fsba(fs, x) \
514 (fs2h32((fs)->e2fs_gd[ino_to_cg((fs), (x))].ext2bgd_i_tables) + \
515 (((x) - 1) % (fs)->e2fs.e2fs_ipg) / (fs)->e2fs_ipb)
516#define ino_to_fsbo(fs, x) (((x) - 1) % (fs)->e2fs_ipb)
517
518/*
519 * Give cylinder group number for a file system block.
520 * Give cylinder group block number for a file system block.
521 */
522#define dtog(fs, d) (((d) - (fs)->e2fs.e2fs_first_dblock) / (fs)->e2fs.e2fs_fpg)
523#define dtogd(fs, d) \
524 (((d) - (fs)->e2fs.e2fs_first_dblock) % (fs)->e2fs.e2fs_fpg)
525
526/*
527 * The following macros optimize certain frequently calculated
528 * quantities by using shifts and masks in place of divisions
529 * modulos and multiplications.
530 */
531#define ext2_blkoff(fs, loc) /* calculates (loc % fs->e2fs_bsize) */ \
532 ((loc) & (fs)->e2fs_qbmask)
533#define ext2_lblktosize(fs, blk) /* calculates (blk * fs->e2fs_bsize) */ \
534 ((blk) << (fs)->e2fs_bshift)
535#define ext2_lblkno(fs, loc) /* calculates (loc / fs->e2fs_bsize) */ \
536 ((loc) >> (fs)->e2fs_bshift)
537#define ext2_blkroundup(fs, size) /* calculates roundup(size, fs->e2fs_bsize) */ \
538 (((size) + (fs)->e2fs_qbmask) & (fs)->e2fs_bmask)
539#define ext2_fragroundup(fs, size) /* calculates roundup(size, fs->e2fs_bsize) */ \
540 (((size) + (fs)->e2fs_qbmask) & (fs)->e2fs_bmask)
541/*
542 * Determine the number of available frags given a
543 * percentage to hold in reserve.
544 */
545#define freespace(fs) \
546 ((fs)->e2fs.e2fs_fbcount - (fs)->e2fs.e2fs_rbcount)
547
548/*
549 * Number of indirects in a file system block.
550 */
551#define EXT2_NINDIR(fs) ((fs)->e2fs_bsize / sizeof(uint32_t))
552
553#endif /* !_UFS_EXT2FS_EXT2FS_H_ */